System and method for local surface treatment

ABSTRACT

The invention relates to a system for the local surface treatment of an aeronautical part ( 1 ) to be treated. 
     Said system is characterised in that it comprises a plurality of containers ( 18, 19, 20, 21 ) each comprising a treatment product ( 22, 23, 24, 25 ), at least one bath enclosure ( 102   a,    102   b ) suitable for delimiting a fluid-tight space ( 26   a,    26   b ) between this bath enclosure ( 102   a,    102   b ) and a portion ( 101   a,    101   b ) of the part to be treated, and a controlled circuit ( 10 ) for supplying said fluid-tight space ( 26   a,    26   b ) with treatment product ( 22, 23, 24, 25 ) the containers ( 18, 19, 20, 21 ) connecting at least this container ( 18, 19, 20, 21 ) to said fluid-tight space ( 26   a,    26   b ) and comprising valves for managing the supply to the fluid-tight space by one or more containers from the plurality of containers.

1. TECHNICAL FIELD OF THE INVENTION

The invention relates to systems and to methods for the local surface treatment of industrial parts. In particular, the invention relates to systems and to methods for the local treatment of metal parts intended for aeronautical use.

2. TECHNOLOGICAL BACKGROUND

The treatment of surfaces of parts, in particular metal parts, consists of applying, to the surface of a part, one or more treatment products in order to form a coating, of which the objective is improving the protection of the part, for example against corrosion, better chemical resistance or mechanical strength, etc., or a modification to the external appearance of the part, for example by applying a coat of paint.

Generally, the coating is formed by applying the treatment products to the part by dipping said part in one of more baths each comprising a treatment product. The baths are located in vessels suited to the size of the part to be treated. This dipping method is already tried and tested in the aeronautical field and makes it possible to obtain qualified coatings in accordance with the constraints of this field, in particular in terms of performance and environmental constraints.

Nevertheless, the main drawback of these treatments by dipping in a bath is that they do not allow the application of a localised surface treatment on only one or more portions of the part. In addition, the size of the vessel containing the bath limits the size of the part that can be treated.

Solutions have been proposed to solve this problem.

For example, devices allow the local application of a treatment product by the use of pads soaked in this treatment product. However, these devices are used by manual application to the portion of the part to be treated. The application times are therefore lengthy and incompatible with a mass production line. In addition, manual application is not very reproducible, and can cause runs liable to contaminate and damage zones peripheral to those treated. Finally, these applications have not been systematically certified in the aeronautical field, and cannot therefore be used to form certain types of coating.

Another solution proposed is treatment by thermal spraying. Nevertheless, this solution requires expensive investment, in particular because of the equipment used (automated means, systems under controlled atmosphere, plasma torches, etc.) and has not been certified in the aeronautical field. In addition, this solution can be used only on the production site and not for direct repair on another site.

3. OBJECTIVES OF THE INVENTION

The invention aims to overcome at least some of the drawbacks of the known systems and methods for local surface treatment.

In particular, the invention also aims to provide, in at least one embodiment of the invention, a system and method for local surface treatment that allow local treatment of large-sized parts.

The invention also aims to provide, in at least one embodiment, a system and method for local surface treatment that allow local treatment that does not bring into question the quality of the coating formed, compared with dipping in a bath.

The invention also aims to provide, in at least one embodiment of the invention, a mobile system and method for local surface treatment, that is to say a system and method that can be moved and used on a production site, a repair site, a maintenance site, etc.

The invention also aims to provide, in at least one embodiment, a system and method for local surface treatment guaranteeing the absence of treatment product running onto surfaces not requiring treatment.

The invention also aims to provide, in at least one embodiment, a system and method for local surface treatment that can be used on mass production lines.

The invention also to provide, in at least one embodiment, an efficient system and method for local surface treatment.

The invention also aims to provide, in at least one embodiment, an inexpensive system and method for local surface treatment.

4. DISCLOSURE OF THE INVENTION

For this purpose, the invention relates to a system for the local surface treatment of an aeronautical part to be treated, characterised in that it comprises:

-   -   a plurality of containers, each comprising a treatment product,     -   at least one bath enclosure suitable for delimiting a         fluid-tight space between this bath enclosure and a portion of         the part to be treated,     -   a controlled circuit for supplying said fluid-tight space with         treatment product from at least one container, connecting the         containers to said fluid-tight space and comprising valves for         managing the supply to the fluid-tight space by one or more         containers from the plurality of containers.

Aeronautical part is understood to mean a part installed on an aircraft or intended to be installed on an aircraft.

A local surface treatment system according the invention therefore makes it possible to treat a part to be treated by means of a treatment product by directly fitting a bath to the part to be treated by means of the bath enclosure, which makes it possible to apply the treatment product to the portion of the part desired to be treated. The bath enclosure further allows the application of the treatment product in various situations, in particular on a portion of the part directed towards the ground. The impermeability of the fluid-tight space delimited by the enclosure makes it possible to avoid runs on other portions of the part to be treated that do not require treatment.

The local surface treatment system allows the use of treatment products identical to those used in bath dipping techniques for local application. Thus, in the aeronautical field, the local surface treatment system according to the invention does not bring into question the quality and any certifications of the treatment compared with bath dipping. Furthermore, the speed, cost and energy consumption of the local surface treatment system are substantially equivalent to the bath dipping of the prior art. The local surface treatment system is suitable for mass production, and can be automated, for example by means of robotic arms for bringing the bath enclosure to the surface to be treated.

The treatment products used are for example products that make it possible to limit the risks and effects of corrosion, to facilitate the subsequent application of another treatment product, to provide aesthetic quality to the part to be treated, to improve the chemical and mechanical resistance to environmental conditions, etc.

The use of a bath enclosure further makes it possible to carry out local treatment on parts of any size, in particular for example directly on an aircraft on a maintenance or repair site, without having to isolate the part to be treated. The shape of the bath enclosure can be adapted for the treatment of parts to be treated of various shapes, for example planar, curved or cylindrical (in particular for pipework).

The presence of a plurality of containers allows the successive or simultaneous application of a plurality of treatment products each coming from a different container. If certain treatment products must not be mixed, the controlled supply circuit can be configured so as not to supply the fluid-tight space simultaneously with these products. One of the containers may further comprise a rinsing product that makes it possible to avoid the mixing of treatment products. One of the containers may further comprise a pickling product used first in the treatment to allow the treatment of parts to be treated that already have one or more coats of paint.

Advantageously and according to the invention, at least one bath enclosure, in particular each bath enclosure, comprises a wall having an opening, adapted for covering the portion of the part to be treated so that the fluid-tight space is delimited by the wall of the bath enclosure on the one hand and the portion of the part to be treated on the other hand.

According to this aspect of the invention, the opening allows an arrangement of the enclosure of the part portion to be treated, this part portion fulfilling the role of closure of the enclosure in order to form the fluid-tight space.

Advantageously and according to the invention, the opening is surrounded by seals.

According to this aspect of the invention, the seals make it possible to improve the sealing of the fluid-tight space, in order to avoid runs of treatment product onto portions of the part that do not have to be treated by the treatment product.

Advantageously and according to the invention, at least one bath enclosure, in particular each bath enclosure, comprises a device for controlling the temperature in the fluid-tight space, said control device comprising heating means and temperature-measurement means.

According to this aspect of the invention, the device makes it possible to control the temperature inside the fluid-tight space, for example if the treatment product requires to be used under particular conditions, or to check the correct performance of the treatment in the fluid-tight space by controlling the temperature or variations in temperature.

Advantageously and according to the invention, at least one bath enclosure, in particular each bath enclosure, comprises means for stirring the treatment product in the fluid-tight space.

According to this aspect of the invention, the stirring means make it possible to homogenise the treatment product to allow identical application to the whole of the portion of the part to be treated.

Advantageously and according to the invention, the aeronautical part is a large-sized part.

Large-sized part means a part of which the dimensions are large compared with a human operator, one that is difficult to handle or cannot be handled or manoeuvred by a human operator because of its large dimensions and generally requiring the use of robotic elements such as robotic arms to be manipulated. The overall size of parts having large dimensions requires in particular the manipulation or manoeuvring thereof in suitable spaces and equipment, such as hangers.

In particular, a large-sized aeronautical part is, for example, the elements of a cell of an aircraft, that is to say a fuselage, a wing (or wing unit), a tail unit, or the complete cell itself, when the aircraft is assembled.

Advantageously, a system according to the invention comprises a plurality of bath enclosures suitable for delimiting a plurality of fluid-tight spaces between the plurality of bath enclosures and a plurality of portions of the part to be treated.

According to this aspect of the invention, the presence of a plurality of bath enclosures allows the simultaneous application of the same treatment product, or of a mixture of treatment products, on a plurality of portions of the part to be treated. This makes it possible to greatly improve the speed of treatment of the surfaces, by simultaneous treatment, using a single system for all the treatments to be performed. Furthermore, the bath enclosures may have different shapes to adapt to parts to be treated of different shapes.

Advantageously, a system according to the invention comprises an electricity generator comprising a negative pole connected to at least one bath enclosure, in particular each bath enclosure, and a positive pole connected to the part to be treated.

According to this aspect of the invention, the generator allows treatments by anodisation of the part, particularly when the part is metal, the part fulfilling the role of an anode and the bath enclosure fulfilling the role of a cathode, and the treatment product being an electrolytic solution filling the fluid-tight space between the part to be treated and the bath enclosure during the anodising treatment. The negative pole is connected to the bath enclosure, for example by means of a connector screwed into the wall of the bath enclosure,

Advantageously, a system according to the invention comprises a filtration device arranged on the controlled supply circuit.

According to this aspect of the invention, the filtration device allows the decontamination of a treatment product already used before reinjecting said product into the supply circuit.

The invention also relates to a method for the local surface treatment of an aeronautical part to be treated, comprising a step of applying at least one treatment product to a portion of the part to be treated, characterised in that it comprises, prior to the application step:

-   -   a step of fitting a bath enclosure on the part to be treated, so         as to delimit a fluid-tight space between the bath enclosure and         the portion of the part to be treated,     -   a step of supplying the fluid-tight space with at least one         treatment product, said treatment product coming from one or         more containers, each comprising a treatment product.

Advantageously, the local treatment method according to the invention is implemented by the local treatment system according to the invention.

Advantageously, the local treatment system according to the invention implements the local treatment method according to the invention.

The invention also relates to a local treatment system and a local treatment method characterised in combination by all or some of the features mentioned above or below.

The invention is suitable for any part that is to undergo surface treatment, whatever the field concerned, and in particular parts intended for aeronautical, naval, automobile, railway, applications, etc.

5. LIST OF FIGURES

Other aims, features and advantages of the invention will become apparent from a reading of the description given solely by way of a non-limiting example and which refers to the accompanying figures, in which:

FIG. 1 is a schematic view in cross section of a local surface treatment system according to a first embodiment of the invention,

FIG. 2 is a schematic view in cross section of a local surface treatment system according to a second embodiment of the invention,

FIG. 3 is a schematic view of a local surface treatment method according to one embodiment of the invention.

6. DETAILED DESCRIPTION OF AN EMBODIMENT OF THE INVENTION

The following embodiments are examples. Although the description refers to one or more embodiments, this does not necessarily mean that each reference relates to the same embodiment or that the features apply only to one embodiment. Simple features of various embodiments can also be combined in order to form other embodiments.

FIG. 1 depicts schematically in cross section a system 100 for the local surface treatment of a portion 101 a, 101 b of a part 1 to be treated according to a first embodiment of the invention.

The system 100 makes it possible to treat a part 1 to be treated by means of treatment products 22, 23, 24, 25, each treatment product 22, 23, 24, 25 being respectively stored in a container 18, 19, 20, 21. The part 1 to be treated is, for example, a metal part forming part of an aircraft.

To carry out local treatment of the part 1 to be treated, for example on one or more portions 101 a, 101 b of the part to be treated, the local treatment system 100 comprises one or more bath enclosures, for example two bath enclosures 102 a, 102 b in this first embodiment, each being located on a face of the part 1 to be treated. Each bath enclosure 102 a, 102 b delimits a fluid-tight space 26 a, 26 b between walls 7 a, 7 b of each bath enclosure 102 a, 102 b and the portion 101 a, 101 b of the part to be treated. Each bath enclosure 102 a, 102 b comprises an opening adapted to cover the portion 101 a, 101 b of the part to be treated so as to close the fluid-tight space 26 a, 26 b.

The opening is surrounded by seals 8, making to it possible to avoid runs of one of the treatment products onto zones of the part to be treated other than the portion 101 a, 101 b of the part to be treated. These seals 8 can be produced for example by means of an adhesive of the adhesive masking tape type affording protection of the part 1 to be treated, or by means of electromagnetic suckers, affording connection with the part 1 to be treated, covered with an elastomer material providing the seal, or by means of a mechanical mount compressing a seal.

The containers 18, 19, 20, 21 are connected to each fluid-tight space 26 a, 26 b by a controlled supply circuit 10. The controlled supply circuit comprises a set of valves, here solenoid valves 35, allowing the supply of one or more fluid-tight spaces 26 a, 26 b with treatment products 22, 23, 24, 25 coming from one or more containers 18, 19, 20, 21. The treatment products 22, 23, 24, 25 are conveyed in the supply circuit by means of pumps 33, one per container, and connected to the containers by pipes 14, 15, 16, 17. A programmable controller 34 controls the opening and closing of the solenoid valves 35 and the functioning of the pumps 33 (start/stop, flow rate, etc.).

The controlled supply circuit 10 is connected to the fluid-tight spaces 26 a, 26 b by supply and discharge pipes 9 a, 9 b. These supply and discharge pipes 9 a, 9 b pass through the walls 7 a, 7 b of the bath enclosures 102 a, 102 b to allow the supply of treatment product 22, 23, 24, 25 to the fluid-tight spaces 26 a, 26 b. The discharge of the treatment products takes place through the supply and discharge pipes 9 a, 9 b by means of plungers 38 or by a simple discharge cap (not shown) and by acting on the relative slope of the bath enclosure allowing total discharge of the treatment product 22, 23, 24, 25 present in the fluid-tight space 26 a, 26 b. Two other additional supply and discharge pipes 9 c and 9 d are shown, having the same features as the supply and discharge pipes 9 a, 9 b. The additional supply and discharge pipe 9 d is connected for example to a bath enclosure, not shown, and the additional supply and discharge pipe 9 c is equipped with a filtration device comprising for example a filter and an oil separator (neither being shown) and for decontaminating a treatment product already used, for example, before reinjecting said product into the supply circuit.

The local surface treatment system 100 makes it possible to carry out various types of local treatment on the part 1 to be treated. To do this, the containers 18, 19, 20, 21 contain different types of treatment product 22, 23, 24, 25, for example, in this embodiment:

-   -   the container 18 comprises an alkaline degreasing product 22,     -   the container 19 comprises demineralised water 23,     -   the container 20 comprises a pickling product 24 composed of         sodium acid,     -   the container 21 comprises a deoxidation product 25.

Other containers, not shown, may contain other types of treatment product.

Furthermore, to allow treatments by anodisation, the system 100 comprises an electricity generator 2, of which a negative pole is connected to the walls of the bath enclosures 102 a, 102 b via points 6 of connection to the enclosures and by means of cathode cables 3, and of which a positive pole is connected to the part 1 to be treated via a point 5 of connection to the part and by means of anode cables 4. Thus the bath enclosures 102 a, 102 b form cathodes and the part 1 to treated forms an anode for treatment by anodisation. During such treatment, the fluid-tight spaces 26 a, 26 b are filled with a treatment product serving as an electrolytic solution. The electric current supply of the electricity generator is read by an ammeter 32, and the voltage thereof is read by a voltmeter 31.

Various sensors and items of equipment are present on the bath enclosures 102 a, 102 b and allow monitoring and control of various parameters related to the application of the treatment product in each fluid-tight space. For example, each bath enclosure 102 a, 102 b comprises:

-   -   heating means, here an electric resistor 12 supplied by a         current generator 11, for heating the treatment product present         in the fluid-tight space,     -   temperature-measurement means, here a temperature sensor 27, for         measuring the temperature, and forming with the resistor 12 a         temperature control device,     -   a timer 28 for measuring the time at which the treatment product         is applied,     -   stirring means, here a filtered-air stirrer 29, for homogenising         the treatment product,     -   spray nozzles 36 for spraying treatment product onto the portion         of the part to be treated,     -   a temperature control system 37, immersed in the bath and         designed so as to have components resistant to the treatment         products used.

The containers 18, 19, 20, 21 may also each comprise sensors and/or equipment of this type, for example a resistor 12, a temperature sensor 27 and a temperature control system 37.

FIG. 2 is a schematic cross section of a local surface treatment system 104 according to a second embodiment. This second embodiment repeats the elements of the first embodiment described in FIG. 1. The elements already described above are not described again and bear the same references. The different elements are described below.

In this second embodiment, a single bath enclosure 105 is shown for treating a cylindrical part 106 to be treated, for example a pipe element. The part 106 to be treated is surrounded by the bath enclosure 105, and the bath enclosure 105 comprises a wall formed by portions 7 c and 7 d, joined by seals 8, for example electromagnetic suckers. The fixing of the two portions 7 c, 7 d of the wall is also reinforced by the addition of mounting flanges 40. The cylindrical part 106 to be treated is inserted in the bath enclosure through a circular opening having the same diameter as the cylindrical part 106 to be treated (not visible in the cross-sectional view). For reasons of legibility in the cross section shown in FIG. 2, the point 5 of connection to the part is shown inside the part, but the point 5 of connection to the part is advantageously located on a portion of the part that is not surrounded by the bath enclosure 105. The connection point 5 may also be located on a metal support for the part (not shown), on which the part rests during treatment.

The bath enclosure 105 according to this embodiment therefore allows treatment of an external portion of the cylindrical part 106 to be treated.

FIG. 3 shows schematically a local surface treatment method 107 according to an embodiment of the invention. The local surface treatment method 107 comprises a step 108 of fitting a bath enclosure on the part to be treated, so as to delimit a fluid-tight space 26, 26 a, 26 b as shown in FIGS. 1 and 2, between the bath enclosure and the portion of the part to be treated. The local surface treatment method 107 next comprises a step 109 of supplying the fluid-tight space with a treatment product by means of the controlled supply circuit 10 as shown in FIGS. 1 and 2, and then a step 110 of applying the treatment product to a portion of the part to be treated.

The invention is not limited solely to the embodiments described. In particular, the number of containers and bath enclosures in the system may vary according to requirements, as well as the number and type of treatment products used, the number of sensors and appliances present on the bath enclosure in the fluid-tight spaces delimited by these bath enclosures, and/or on the containers, etc. Furthermore, the plurality of bath enclosures may make it possible to treat simultaneously not only a plurality of portions of the same part to be treated but also a plurality of different portions of parts to be treated, which makes it possible for example to accelerate the production rate in the context of mass production by allowing the treatment of a plurality of parts simultaneously. 

1. A system for the local surface treatment of an aeronautical part to be treated, the system comprising: a plurality of containers each comprising a treatment product; at least one bath enclosure suitable for delimiting a fluid-tight space between the at least one bath enclosure and a portion of an aeronautical part to be treated; and a controlled circuit supplying said fluid-tight space with said treatment product from at least one of the plurality of containers, and connecting the plurality of containers to said fluid-tight space said controlled circuit comprising valves managing a supply of said treatment product to the fluid-tight space by one or more ones of the plurality of containers.
 2. The local surface treatment system according to claim 1, wherein the at least one bath enclosure comprises a wall having an opening, adapted to cover the portion of the aeronautical part to be treated so that the fluid-tight space is delimited by the wall of the at least one bath enclosure and the portion of the aeronautical part to be treated.
 3. The local surface treatment system according to claim 2, wherein the opening is surrounded by seals.
 4. The local surface treatment system according to claim 1, wherein the at least one bath enclosure comprises a device controlling a temperature in the fluid-tight space, said device comprising a heater and a temperature measurer.
 5. The local surface treatment system according to claim 1, wherein the at least one bath enclosure comprises a stirrer stirring the treatment product in the fluid-tight space.
 6. The local surface treatment system according to claim 1, wherein the aeronautical part to be treated is a large-sized part.
 7. The local surface treatment system according to claim 1, wherein the at least one batch enclosure comprises a multiplicity plurality bath enclosures adapted to delimit a plurality of fluid-tight spaces between each of the multiplicity of bath enclosures and a plurality of portions of the aeronautical part to be treated.
 8. The local surface treatment system according to claim 1, further comprising an electricity generator comprising a negative pole connected to the at least one bath enclosure and a positive pole connected to the aeronautical part to be treated.
 9. The local surface treatment system according to claim 1, further comprising a filtration device arranged on the controlled supply circuit.
 10. A method for the local surface treatment of an aeronautical part to be treated, in which at least one treatment product is applied to a portion of the aeronautical part to be treated, the method comprising: prior to the application of the at least one treatment product to the portion of the aeronautical part to be treated, fitting a bath enclosure on the aeronautical part to be treated, so as to delimit a fluid-tight space between the bath enclosure and the portion of the aeronautical part to be treated; and, supplying the fluid-tight space from one or more containers with the at least one treatment product. 